1. Field of the Invention
The present invention relates to an auxiliary power unit starting apparatus for an electric bicycle, more particularly to a starting apparatus that can convert the rider's pedaling force into mechanical displacement at the time the rider is pedaling the bicycle, and the mechanical displacement can start the auxiliary power unit of the electric bicycle.
2. Description of the Prior Arts
Electric bicycle is very popular with all age groups due to it is environment friendly and has the advantage of and easy operation. So far, there are various methods and times of starting the auxiliary power unit of an electric bicycle.
For example, the electric bicycle in the early days was always provided at the left handlebar with a switch that is to be controlled by the user, however, the operation of it is not easy since the user has to control the switch by hand. Therefore, JP Patent Application 20001-055399 discloses a method of detecting the running resistance and the running speed by using precision-control unit, and then the running data collected and calculated by the precision-control unit is used to control the time of starting the motor. Besides, JP Patent Applications 2001-301293 and 09-268415 also disclose a method of controlling the time of starting the motor based on the running data that are measured by dynamometer, logic circuit and the like electronic element.
Another method is disclosed in JP Patent application 11-290777, in which, an idler shaft is disposed parallel to and between the crank axle and the output axle, and pedaling-force measuring device is mounted on the idler shaft for measuring the pedaling force applied to the crank axle, and then the motor starting time is controlled based on the pedaling force.
As mentioned above, for most of the conventional electric bicycles, their time of starting the auxiliary power unit is controlled by precision-control electronic componentor sensor that is used to detect the running resistance or the pedaling force, and then the time of starting the auxiliary power unit is controlled based on the running data. However, by using the electronic precision electronic elements and complicated measuring instruments, the cost and the failure rate will be accordingly high. Furthermore, by using electronic component to judge the pedaling force of the rider, would probably give rise to a false judgment. For example, the riders of all age groups may have different pedaling force, so if the reference value of the pedaling force is set at a over high level, it will be resulted in an uneasy operation, and if the reference value of the pedaling force is set at a too low level, it will result in a false starting time of starting the motor.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.